Yes, be careful on what the opposition will argue. I would be looking to come at it as 'even if it is property, there is no dishonesty (2 tier R v Ghosh 1982 test) and although edgy, no intention to permanently deprive. If I were you, I'd also be arguing the policy of 'This case would allow anyone to carelessly borrow things if decided against us'- don't forget, you can always attack your opposition's cases and arguments if you have rebuttal. I always used to find it was easier only having notes...